ios8使用ALAssetsLibrar创建单独文件夹方法以及删除文件夹闪退的bug
在ios8以下的系统创建新相册，然后在相册中手动删除了这个"琳小兮"相册，再使用下面的代码重新创建"琳小兮"相册是没有问题的：
[assetsLibrary addAssetsGroupAlbumWithName:@"琳小兮"
resultBlock:^(ALAssetsGroup *group)
{
[groups addObject:group];
}
failureBlock:nil];
ios8+ 包含ios8系统，若文件夹已被手动删除，再创建同名文件夹的时候用上面的代码则会崩溃，需要额外添加Photos.framework框架，并导入头文件#import <Photos/Photos.h>，主要修改的代码部分是把上面那段代码做如下修改：
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^
{
[PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:@"琳小兮"];
} completionHandler:^(BOOL success, NSError *error)
{
if (!success) {
NSLog(@"---error:%@",error.userInfo);
}
}];
下面是完整的demo，结合了网上的实例写的，给大家做一个参考：
1.添加AssetsLibrary.framework 和 Photos.framework框架
2.导入头文件
#import <AssetsLibrary/AssetsLibrary.h>
#import <Photos/Photos.h>
3.代码如下：
@interface ViewController ()<UIActionSheetDelegate>
{
NSMutableArray *imageArray; //存图片的数组
int selectedImageIndex; //当前长按的下标
}
@end
@implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
imageArray = [[NSMutableArray alloc] initWithObjects:[UIImage imageNamed:@"1.png"],[UIImage imageNamed:@"2.png"],[UIImage imageNamed:@"3.png"],[UIImage imageNamed:@"4.png"], nil];
[self initImageView];
}
#pragma mark - 创建UI
-(void)initImageView
{
for (int i = 0; i < imageArray.count; i ++) {
UIImageView * _imageV = [[UIImageView alloc] initWithFrame:CGRectMake(100, 50+110*i, 80, 80)];
_imageV.image = imageArray[i];
_imageV.userInteractionEnabled = YES;
_imageV.tag = 100+i;
[_imageV addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPress:)]];
[self.view addSubview:_imageV];
}
}
#pragma mark - 在手机相册中创建新相册
- (void)createAlbumInPhoneAlbum:(UIImage *)senderImage
{
ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init];
NSMutableArray *groups=[[NSMutableArray alloc]init];
ALAssetsLibraryGroupsEnumerationResultsBlock listGroupBlock = ^(ALAssetsGroup *group, BOOL *stop)
{
if (group)
{
[groups addObject:group];
}
else
{
BOOL haveHDRGroup = NO;
for (ALAssetsGroup *gp in groups)
{
NSString *name =[gp valueForProperty:ALAssetsGroupPropertyName];
if ([name isEqualToString:@"琳小兮"])
{
haveHDRGroup = YES;
}
}
if (!haveHDRGroup)
{
//添加一个新的相册
//此方法在ios8.0系统上，之前用代码创建的相册，手动删除它，再用这个库去创建刚被删除的相册，这个时候方法回调是不会跑fail模块的，它走的是正常流程，但是带回来的group却是nil
// [assetsLibrary addAssetsGroupAlbumWithName:@"琳小兮"
// resultBlock:^(ALAssetsGroup *group)
// {
// NSLog(@"--------%@",group);
// [groups addObject:group];
// }
// failureBlock:nil];
//为了解决iOS8.0以上系统下无法通过代码创建被删除过的同名相册
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^
{
[PHAssetCollectionChangeRequest creationRequestForAssetCollectionWithTitle:@"琳小兮"];
} completionHandler:^(BOOL success, NSError *error)
{
if (!success) {
NSLog(@"---error:%@",error.userInfo);
}
}];
haveHDRGroup = YES;
}
}
};
[assetsLibrary enumerateGroupsWithTypes:ALAssetsGroupAlbum usingBlock:listGroupBlock failureBlock:nil];
[self saveToAlbumWithMetadata:nil imageData:UIImagePNGRepresentation(senderImage) customAlbumName:@"琳小兮" completionBlock:^
{
//这里可以创建添加成功的方法
[self showAlert:@"图片保存成功！"];
}
failureBlock:^(NSError *error)
{
//添加失败一般是由用户不允许应用访问相册造成的，这边可以取出这种情况加以判断一下
if([error.localizedDescription rangeOfString:@"User denied access"].location != NSNotFound ||[error.localizedDescription rangeOfString:@"用户拒绝访问"].location!=NSNotFound){
[self showAlert:error.localizedFailureReason];
}
}];
}
#pragma mark 保存图片
- (void)saveToAlbumWithMetadata:(NSDictionary *)metadata
imageData:(NSData *)imageData
customAlbumName:(NSString *)customAlbumName
completionBlock:(void (^)(void))completionBlock
failureBlock:(void (^)(NSError *error))failureBlock
{
ALAssetsLibrary *assetsLibrary = [[ALAssetsLibrary alloc] init];
void (^AddAsset)(ALAssetsLibrary *, NSURL *) = ^(ALAssetsLibrary *assetsLibrary, NSURL *assetURL) {
[assetsLibrary assetForURL:assetURL resultBlock:^(ALAsset *asset) {
[assetsLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop) {
if ([[group valueForProperty:ALAssetsGroupPropertyName] isEqualToString:customAlbumName]) {
[group addAsset:asset];
if (completionBlock) {
completionBlock();
}
}
} failureBlock:^(NSError *error) {
if (failureBlock) {
failureBlock(error);
}
}];
} failureBlock:^(NSError *error) {
if (failureBlock) {
failureBlock(error);
}
}];
};
[assetsLibrary writeImageDataToSavedPhotosAlbum:imageData metadata:metadata completionBlock:^(NSURL *assetURL, NSError *error) {
if (customAlbumName) {
[assetsLibrary addAssetsGroupAlbumWithName:customAlbumName resultBlock:^(ALAssetsGroup *group) {
if (group) {
[assetsLibrary assetForURL:assetURL resultBlock:^(ALAsset *asset) {
[group addAsset:asset];
if (completionBlock) {
completionBlock();
}
} failureBlock:^(NSError *error) {
if (failureBlock) {
failureBlock(error);
}
}];
} else {
AddAsset(assetsLibrary, assetURL);
}
} failureBlock:^(NSError *error) {
AddAsset(assetsLibrary, assetURL);
}];
} else {
if (completionBlock) {
completionBlock();
}
}
}];
}
#pragma mark - 长按手势
-(void)longPress:(UILongPressGestureRecognizer *)recognizer
{
//当长按手势结束的时候触发
if(recognizer.state == UIGestureRecognizerStateEnded)
{
UILongPressGestureRecognizer *tempLP = (UILongPressGestureRecognizer *)recognizer;
//获得该手势被添加到哪个View
UIImageView *imageV = (UIImageView *)tempLP.view;
selectedImageIndex = (int)imageV.tag-100;
NSLog(@"当前选中的是第%d张图片",selectedImageIndex);
UIActionSheet *menu = [[UIActionSheet alloc] initWithTitle:nil
delegate:self
cancelButtonTitle:@"取消"
destructiveButtonTitle:nil
otherButtonTitles:@"保存到手机",nil];
menu.actionSheetStyle = UIActionSheetStyleBlackTranslucent;
[menu showInView:self.view];
}
}
#pragma mark UIActionSheetDelegate
- (void)actionSheet:(UIActionSheet *)actionSheet clickedButtonAtIndex:(NSInteger)buttonIndex
{
switch (buttonIndex) {
case 0:
{
[self createAlbumInPhoneAlbum:imageArray[selectedImageIndex]];
}
break;
default:
break;
}
}
#pragma mark encapsulationAlert
-(void)showAlert:(NSString *)altString
{
UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:@"提示" message:altString delegate:nil cancelButtonTitle:@"确定" otherButtonTitles: nil];
[alertView show];
}